Table 4. Trial characteristics associated with use of PROs as primary or secondary outcomes, compared to not used.
| PROs as primary, coprimary, or secondary outcome (N = 235) | PROs not useda (N = 180) | Prevalence ratio (95% CI) | P valueb | |
|---|---|---|---|---|
|
Trial age group ≤18 years >65 years Other or mixture |
14 (42.4%) 22 (44.0%) 199 (59.9%) |
19 (57.6%) 28 (56.0%) 133 (40.1%) |
0.71 (0.47 to 1.06) 0.73 (0.53 to 1.02) Reference |
0.0056 |
|
Study setting Clinical Nonclinical or other |
187 (57.0%) 50 (56.2%) |
141 (43.0%) 39 (43.8%) |
1.01 (0.83 to 1.25) Reference |
0.8882 |
|
Trial design Individually randomized Cluster randomized |
171 (64.8%) 66 (43.1%) |
93 (35.2%) 87 (56.9%) |
1.50 (1.23 to 1.84) Reference |
<0.001 |
|
Country of recruitment LMIC only Non-LMIC or mixture |
16 (39.0%) 221 (58.8%) |
25 (61.0%) 155 (41.2%) |
0.66 (0.45 to 0.98) Reference |
0.0153 |
|
Region North America only Europe only Other or mixture |
106 (54.6%) 87 (69.0%) 44 (45.4%) |
88 (45.4%) 39 (31.0%) 53 (54.6%) |
1.20 (0.94 to 1.55) 1.52 (1.19 to 1.95) Reference |
0.0013 |
|
Type of interventionc Clinical Dietary or behavioral Other or mixture |
60 (54.1%) 93 (60.0%) 82 (55.0%) |
51 (45.9%) 62 (40.0%) 67 (45.0%) |
0.98 (0.78 to 1.23) 1.09 (0.90 to 1.32) Reference |
0.5568 |
|
Primary purposed Treatment Prevention Health services research Other |
109 (69.4%) 27 (34.6%) 50 (54.3%) 51 (56.7%) |
48 (30.6%) 51 (65.4%) 42 (45.7%) 39 (43.3%) |
1.23 (0.99 to 1.51) 0.61 (0.43 to 0.87) 0.96 (0.74 to 1.24) Reference |
<0.001 |
|
Type of funder Government, university Yes No Industry Yes No Foundation, special interest group, or other Yes No |
188 (58.4%) 49 (51.6%) 68 (54.4%) 169 (57.9%) 33 (43.4%) 204 (59.8%) |
134 (41.6%) 46 (48.4%) 57 (45.6%) 123 (42.1%) 43 (56.6%) 137 (40.2%) |
1.13 (0.91 to 1.40) Reference 0.94 (0.78 to 1.13) Reference 0.73 (0.55 to 0.95) Reference |
0.2392 0.5114 0.0090 |
| Impact factor e | 5.1 (3.1, 15.3) | 6.0 (3.9, 20.8) | NA | 0.0458f |
|
Patient/public engagement Yes No or unclear |
26 (66.7%) 211 (55.8%) |
13 (33.3%) 167 (44.2%) |
1.19 (0.94 to 1.52) Reference |
0.1929 |
|
Other stakeholder engagement Yes No or unclear |
28 (53.8%) 209 (57.3%) |
24 (46.2%) 156 (42.7%) |
0.94 (0.72 to 1.23) Reference |
0.6419 |
|
Year 2014–2015 2016–2017 2018–2019 |
59 (55.1%) 100 (60.6%) 78 (53.8%) |
48 (44.9%) 65 (39.4%) 67 (46.2%) |
Reference 1.10 (0.89 to 1.36) 0.98 (0.78 to 1.23) |
0.7394g |
an = 2 trials with unclear use of PROs were included in this group.
bChi-squared test unless otherwise indicated.
cCategories obtained from ClinicalTrials.gov and grouped as follows: Clinical (Drug, Device, Biological, Procedure, Radiation, Genetic, Combination Product, Diagnostic Test); Dietary and behavioral (Dietary Supplement, Behavioral); Other (Other).
dCategories obtained from ClinicalTrials.gov and grouped as follows: Treatment (Treatment); Health Services Research (Health Services Research); Other (Prevention, Diagnostic, Supportive Care, Screening, Basic Science, Educational/Counseling/Training, Other).
eMedian (Q1, Q3).
fWilcoxon rank sum test.
gCochran–Armitage test for trend.
LMIC, low- or middle-income country; PRO, patient-reported outcome.